Quarterly report pursuant to Section 13 or 15(d)

Funds Held for Clients and Corporate Investments (Details 2)

v2.4.0.8
Funds Held for Clients and Corporate Investments (Details 2) (USD $)
In Millions, unless otherwise specified
 3 Months Ended
Aug. 31, 2014
Security
Aug. 31, 2013
May 31, 2014
Security
Maturity Date:      
Due in one year or less, Amortized cost $ 340.6    
Due in one year or less, Fair value 343.3    
Due after one year through three years, Amortized cost 802.4    
Due after one year through three years, Fair value 818.2    
Due after three years through five years, Amortized cost 757.0    
Due after three years through five years, Fair value 768.8    
Due after five years, Amortized cost 826.1    
Due after five years, Fair value 836.8    
Total, Amortized cost 2,726.1    
Fair value 2,767.1   3,391.4
Funds Held for Clients and Corporate Investments (Textual)      
Net unrealized gain on available-for-sale securities 41.0   34.5
Number of available-for-sale securities in an unrealized loss position 58   98
Gross realized gains 0.1 0.2  
Gross realized losses $ 0 $ 0  
Minimum maturity period for VRDNs primarily categorized as due after five years (in years) 20 years    
Maximum maturity period for VRDNs, primarily categorized as due after five years (in years) 30 years